Calcium-containing compounds such as calcium carbonate have been employed in products which are placed in the oral cavity. For example, Chau et al. (U.S. Pat. No. 5,637,313) discloses a chewable dosage form using calcium carbonate as a bulking agent. Gallopo et al. (U.S. Pat. No. 5,077,051) discloses the sustained release of active agents in the form of bioadhesive microcapsules where calcium carbonate is used as a buffering agent. Cuca et al. (U.S. Pat. Nos. 5,670,163 and 5,858,391) disclose long acting gastrointestinal and esophageal protectants which can include mineral substances such as calcium carbonate.
Calcium is a mineral which requires daily replenishing to sustain healthy bones, teeth and the like. Calcium is not readily stored in the body and therefore must be replenished daily such as by eating foods rich in available calcium. The vitamin and nutraceutical industry has for many years provided supplements for daily intake which include a variety of minerals and vitamins including calcium-containing compounds such as calcium carbonate, calcium citrate and the like.
Ingesting the proper minimum dosage requirement of calcium is largely dependent on the discipline of the individual. In particular, the individual must eat a sufficient amount of calcium-containing foods and/or take calcium-containing supplements. In order to maintain a proper level of available calcium in the body, it is often necessary to eat calcium-containing foods and/or calcium-containing supplements multiple times in a single 24 hour period. This presents problems to many individuals who may not be able to eat calcium-containing foods and/or take calcium-containing supplements as required.
It would therefore be a benefit to provide a convenient vehicle for delivering calcium to an individual which can be easily consumed, is readily available, and can be taken by the individual at any time during the day as needed without having to sit down and eat a meal or resort to capsules or tablets containing calcium.
Chewing gum compositions are used by many individuals because they are readily available, easily transported and provide chewing satisfaction. Chewing gum is a convenient product which does not burden the user or require a break from daily routines.
In recent years, chewing gum compositions have been provided with various additives such as, for example, stain removing agents, antibiotics, and mineral supplements including calcium-containing compounds. For example, International Publication No. WO 98/18339 discloses a chewing gum composition containing bone minerals, calcium triphosphate and/or hydroxyapatite in a gum base. The product is used for supplementing dietary calcium for the prevention of osteoporosis, accelerating development of bones and teeth and the like. German Patent Document No. DE3941490 discloses a chewing gum composition with a core uniformly surrounded by a sugar coating containing soluble minerals including one or more of calcium citrate and calcium chloride. A further example is set forth in Cherukuri et al. (U.S. Pat. No. 4,971,806) which discloses a multi-layer chewing gum composition in which the gum base may include mineral adjuvants such as calcium carbonate, dicalcium phosphate and tricalcium phosphate.
A chewing gum composition containing a liquid or semisolid center is generally known as a centerfilled chewing gum composition. One such example is disclosed in Ogawa et al. (U.S. Pat. No. 4,157,402) which discloses that additives such as calcium carbonate may be added to the chewing gum base.
Chewing gum compositions present unique problems in delivering agents contained therein. Such compositions typically comprise a water-insoluble gum base which provides the bulk to the gum composition but which invariably traps agents having compatibility with the gum base. Adding additional amounts of an agent to the gum base to compensate for the amount of the agent trapped therein is problematical because the additional amounts of agents often adversely affect the integrity, sensory and/or taste properties of the gum composition.
It would therefore be a significant advance in the art of forming chewing gum compositions for the delivery of calcium to provide a composition which effectively enables the user to readily consume at least a minimum daily requirement of calcium in a routine manner. It would be another significant advance in the art if a chewing gum composition can provide a sufficient amount of calcium per piece so as to provide the minimum daily dosage requirement with no more than about three pieces of the chewing gum composition per day. It would be a further advance in the art to provide a chewing gum composition including a calcium-containing compound which maintains excellent taste and sensory characteristics.